Study on stress evolution law of upper coal seam in long‐distance advance mining of lower coal seam

With the shift of coal resources to deep mining, occurrence long-distance seams has increased, and protective layer mining is facing new challenges. This paper attempts explain stress evolution law upper group in lower Pingdingshan No. 8 Coal Mine. A simulation model advance lower-group was established. The seam under influence advanced disturbance studied. following conclusions were obtained: had a positive or negative impact on distribution group. recovery F-21030 working face, overburden goaf finally formed “Y” type pressure relief area. effect E-21070 face near stopping line obvious. Group E divided into three areas affected by seam. maximum value 6.6% than initial stress. According results, regions, namely, region, increase original region. field drainage results gas, extraction curve could be parts, stable area, pure gas volume reach seven eight times remarkable, optimal range 22–210 m behind